Expansion joint structure



NOV. 14, 1939. w. F. WILMOTH 2,179,911

EXPANSION JINT STRUCTURE Filed March 5, 1939 Patented Nov. 14, 1939UNITED STATES PATENT mm:

2 Claims.

The invention relates to expansion joints, particularly for use inconcrete pavements and has as an objectthe provision of a pre-formedstructure to be placed upon the subgrade and to act as a form againstwhich the concrete for one section will be cast. a

It is a further object of the invention to provide a structure of theclass described which will be assembled at the factory and which may bei installed by unskilled labor with a, minimum chance of faultyconstruction.

It is a further object of the invention to pro-, vide a structure of theclass described wherein the dowel pins for connecting adjacent sectionsI of concrete will be preserved in correct alignment.

Further objects of the invention will appear from the followingdescription showing an illustrative embodiment of the invention, andwherem:

Figure 1 is a perspective view of the structure partially installed; and

Figure 2 is a vertical transverse section on line 2-2 of Figure 1.

As shown the device comprises a plate Ill of a usual expansion jointmaterial as asphalt-impregnated felt. To support the plate Hi there isshown a metallic plate It having a margin thereof as l2 bent at rightangles, the plate I I being se cured to the plate III as by means ofears 25 struck out from the material of the plate and penetrating theplate Ill and clinched in the manner shown in Figure 2.

In accordance with accepted practice, the present invention is shown asembodying dowel pins l3, l4 penetrating the plates and desirably securedto the plate H as by electric welds ii.

To hold the plates in vertical position against the thrust of the firstcast concrete block as l6, certain of the dowel pins as It are shownextended and bent downwardly as at l! and pro vided in their ends withperforations to receive pins ill to be driven into the sub-grade. Thesebent down portions may be provided upon as many of the dowel pins .asdesired, but every fourth pin as shown is found to be a sumcientfrequency for such supports.

To prevent the bottom of the structure from shifting, pins l9 aredesirably passed through the angular portion l2 of the plate II. It isof great importance in structures of this character that -the dowel pinsare maintained in a position parallel with the surface of the pavementand also parallel with vertical planes normal to the joint. When thestructure is installed, the side of the structure presenting thedownturned portion I1 is exposed while the block i6 is being cast.

In the installation of the structure with unskilled laborers workingthereabout, it is almost certain that some one will step upon theexposed ends of the dowel l3 and unless supported the stepped upon dowelwill be forced out of correct position. To hold the pins in correctposition, there is shown a rod 20 placed along the ends of the dowelpins l3.and connected to each and to 10 the pins It as by electricwelding indicated at 2|.

In accordance with usual practice sleeves 22 are shown placed upon thefree ends of the dowels l3 which will be encased in the concrete andwill preserve a space about the ends of the dowels to prevent theirabutment against the concrete when set to permit of movement of thepavement in expansion and contraction. In accordance with usual practicethe portion of the dowels which carry the sleeves 22, and from saidsleeves up to the plate It, is provided with some type of coating whichwill prevent the bond of the concrete when set from locking the dowelsin the concrete to prevent such movements'of the concrete relative tothe dowels.

As is well understood the importance of maintaining of the dowelscorrectly parallel with the expected movements of the concrete inexpansion' and contraction resides in the fact that if they are at anangle to such movement, the concrete will inevitably break when suchmovements occur.

The structure of the invention may be assembled at the factory and whenshipped to the point of use all that is necessary to assure correctplace- .35 ment is that it be dropped on the subgrade and the pinsdriven through the openings provided therefor. When this is done, thestructure will inevitably stand in the proper position if placed at thepoint indicated by the engineer.

Minor changes may be made in the physical embodiment of the inventionwithout departing from. the spirit thereof.

I claim: I

1. An expansion joint structure comprising, in combination: a plate ofcompressible material;

a metallic plate secured thereto, substantially coextensive therewithformed with a bottom marginal flange having anchoring-pin perforations;a plurality of dowel pins secured to said metallic plate, havingstraight portions extending in both directions from said plates normalthereto; certain of said pins beyond their straight portions and on themetallic plate side of said plates only downwardly deflected to con- 2a,17o,o11

tact. a surface upon which said marginal flange rests at points spacedtherefrom while said plates are perpendicular to the surface; the endsof said downwardly deflected portions having anchorpin receivingperforations whereby free ends of theustraight portions of said dowelpins at one side of the assembly are slidable'in enclosing concrete. v

2. The combination of claim 1 with a bar extending between and securedto the straight portions of said dowel pins in spaced relation to saidplates adjacent the downwardly deflected portions of said certain pins.

WILLIAM F.

